螺旋CT对肾细胞癌亚型的鉴别诊断价值

目的:探讨CT动态增强扫描对肾细胞癌病理亚型的鉴别诊断价值。方法:87例经手术病理证实的肾细胞癌患者,包括50例透明细胞癌、17例乳头状癌、8例嫌色细胞癌和2例集合管癌,术前行CT平扫和双期动态增强扫描(肾皮髓期和肾实质期),测量肿瘤、腹主动脉及邻近正常肾实质的CT值,并计算肿瘤与主动脉、肾实质的强化比值,同时评价肿瘤的强化方式,对不同病理亚型肿瘤的各项指标进行统计学分析。结果:透明细胞癌在皮髓期和实质期增强扫描时肿瘤与主动脉、肾实质的强化比值均高于乳头状癌和嫌色细胞癌(P<0.01),而乳头状癌和嫌色细胞癌间差异均无统计学意义(P>0.05)。不均匀强化常见于透明细胞癌(92%)、乳头状癌(82.4%)和集合管癌(100%);而均匀强化常见于嫌色细胞癌(62.5%),其与透明细胞癌(P=0.010)和乳头状癌(P=0.017)间差异有显著性意义。结论:CT增强扫描时分析肿瘤与主动脉和肾实质的强化比值及强化的均匀度对肾癌病理亚型的鉴别诊断有重要价值。     

肾癌不同亚型CT表现的对照研究

目的探讨肾癌亚型的影像学特征,提高诊断的准确率。方法回顾性分析48例经手术和病理证实的肾细胞癌,其中透明细胞癌28例,乳头状癌12例,嫌色细胞癌8例,均行多层螺旋CT平扫及增强检查,比较平扫、皮髓质期、实质期和排泄期各肾癌亚型坏死、囊变发生率及肿瘤的强化形式及强化幅度。结果透明细胞癌与乳头状癌、嫌色细胞癌在强化幅度上差异有统计学意义(P<0.05),而乳头状癌与嫌色细胞癌强化幅度差异无统计学意义(P>0.05)。透明细胞癌的坏死、囊变发生率显著高于其他两种亚型。动态增强各期透明细胞癌强化程度最高,强化形式呈"快进快出"表现,乳头状癌轻至中度强化,嫌色细胞癌强化最轻,两者均呈渐进性延迟强化;85%透明细胞癌显示不均匀强化或主要周边强化,而41%乳头状癌、87%嫌色细胞癌显示较均匀的强化,三者之间差异有统计学意义(P<0.05)。结论不同的肾癌亚型影像学表现具有一定的特征性,螺旋CT动态增强扫描对诊断有帮助。     

16层螺旋CT三期动态扫描对肾癌亚型的诊断价值初探

目的探讨16层螺旋CT三期动态增强扫描对肾癌亚型的鉴别诊断价值。资料与方法回顾性分析52例肾癌患者的三期动态CT扫描资料,对经手术病理证实的透明细胞癌、乳头状癌、嫌色细胞癌3种肾癌亚型图像进行双盲法对比分析,比较肿瘤的大小、强化程度与模式（均匀、不均匀及主要周边强化）、有无钙化、出血、坏死与囊变、肿瘤扩散及淋巴结转移等情况,同时结合患者的性别和年龄,分析3种亚型肾癌之间的影像学差异。结果透明细胞癌与乳头状癌、嫌色细胞癌在强化程度上差异有统计学意义（P〈0.05）,而乳头状癌与嫌色细胞癌强化程度差异无统计学意义（P〉0.05）。透明细胞癌的坏死、囊变率显著高于其他两种亚型,3种亚型肾癌观察到血管成分的比例分别为21.6%、10%、0%。80%的嫌色细胞癌显示均匀强化,而乳头状癌占40%,透明细胞癌占2.7%,三者之间差异有统计学意义（P〈0.05）。而肿瘤内的钙化成分所占比例三者之间差异无统计学意义（P〉0.05）。结论肿瘤的强化程度是区别肾癌的亚型最有价值的参数,而肿瘤有无钙化、出血、坏死及囊性、血管状况及强化模式对区别肾癌亚型有一定的作用。     

MSCT动态增强在乏脂肪RAML与嫌色细胞肾癌鉴别诊断价值

目的 探讨MSCT动态增强在乏脂肪RAML与嫌色细胞肾癌的鉴别诊断价值.方法 选取经临床病理证实的并有完整临床和CT资料的21例乏脂肪RAML与14例嫌色细胞肾癌,回顾性分析其MSCT表现,测量病灶的各期CT值,并测量病灶相同层面皮质的CT值,并计算病灶CT值与其邻近皮质CT值的比值,统计分析各期CT值及其比值的统计学...     

MSCT三期增强扫描对巨大肾细胞癌病理亚型的鉴别诊断价值

目的：探讨多层螺旋CT（MSCT）三期增强扫描对最大径≥5cm巨大肾细胞癌的鉴别诊断价值。方法回顾性分析本院经手术病理证实的50例最大径≥5cm巨大肾细胞癌患者行M SC T平扫加皮质期、髓质期及排泄期扫描的影像学特征性表现,重点分析CT动态增强扫描技术的应用及强化特点,寻找各病理亚型的影像学异同。结果巨大肾细胞癌出血、坏死囊变明显。透明细胞癌最常见,坏死较多甚而较大,以结节堆积样强化及片样强化为主,强化程度大多高于嫌色细胞癌及乳头状癌、集合管癌等非透明细胞癌;巨大乳头状癌坏死区较小,强化程度较低,相对均匀;嫌色细胞癌密度明显不均匀,强化明显但程度低于透明细胞癌、高于乳头状癌,可见逐渐填充中央疤痕;嫌色细胞癌及乳头状癌很少周围侵犯及转移;集合管癌恶性程度最高,缺乏特异强化形式,强化程度低,极具周围侵犯及淋巴结转移,预后极差。结论巨大肾细胞癌病理亚型的三期增强CT表现各具特征,具有鉴别诊断价值。     

螺旋CT双期增强扫描在肾细胞癌亚型诊断中的价值

目的:评价多层螺旋CT动态双期增强扫描在肾细胞癌亚型鉴别诊断中的作用.方法:回顾性分析106例经手术和病理证实的肾细胞癌患者行多层螺旋CT平扫加皮髓期、实质期双期扫描的影像资料,重点分析CT动态强化方式及类型在各种亚型之间的异同.结果:皮髓期时88.6%(62/70)透明细胞癌、80%(4/5)多房囊性细胞癌及83.3%(5/6)混合型癌呈明显强化;84.6%(11/13)乳头状癌、100%(9/9)嫌色细胞癌、66.7%(2/3)集合管癌轻度强化;91.5%(64/70)透明细胞癌、69.2%(9/13)乳头状癌、80%(4/5)多房囊性细胞癌、83.3%(5/6)混合性癌及100%(3/3)集合管癌呈不均匀或周边强化;而88.9%(8/9)嫌色细胞癌呈均匀强化.皮髓期与实质期两期动态分析示88.6%(62/70)透明细胞癌呈典型"快进快出"表现;84.6%(11/13)乳头状癌呈"延迟强化"的特点.结论:肾细胞癌皮髓期的强化程度在各亚型的鉴别诊断中具有重要的价值,而CT双期扫描中肿瘤的动态强化方式及类型是鉴别各亚型的重要补充依据.     

CT在不同病理亚型肾细胞癌诊断中的价值

目的 探讨WHO病理分类中不同亚型肾细胞癌（renal cee carcinoma,RCC）的CT特征,旨在加深对RCC的认识,提高影像诊断准确率.方法 回顾性分析2008年1月～2013年9月72例经病理证实的RCC患者的临床资料及CT检查结果,其中透明细胞癌58例,乳头状细胞癌7例,嫌色细胞癌4例,多房囊性肾癌3例.结果 透明细胞癌平扫病灶呈等或低密度,增强扫描皮质期肿瘤多呈不均性明显强化,实质期、分泌期强化减退.乳头状细胞癌多呈等密度或囊实性,增强扫描皮质期实性部分轻度强化,实质期、分泌期延迟强化.嫌色细胞癌多位于肾髓质内,密度均匀,增强扫描强化均匀,坏死、囊变少见.多房囊性肾癌位于肾皮质区,由多个囊腔和分隔构成,囊壁及间隔菲薄,无附壁结节,平扫病灶呈低密度,增强扫描囊壁、间隔延迟强化.结论 不同病理亚型肾细胞癌CT特征、手术方案、预后均不同,术前影像学检查准确诊断能够为临床医师选择合理手术方案提供可靠依据.     

Angiomyolipoma with minimal fat: differentiation from renal cell carcinoma at biphasic helical CT

PURPOSE: To compare various computed tomographic (CT) features of angiomyolipoma (AML) with minimal fat with those of size-matched renal cell carcinoma (RCC). MATERIALS AND METHODS: Eighty-one patients (19 with AML with minimal fat [mean diameter, 2.8 cm; range, 1.5-4.5 cm] and 62 with RCC [mean diameter, 3.1 cm; range, 1.8-4.5 cm]) who had undergone biphasic CT (ie, CT with unenhanced, corticomedullary, and early excretory phase scanning) were evaluated. Two reviewers who were unaware of the diagnosis retrospectively recorded tumor attenuation on unenhanced scans, enhancement characteristics (ie, homogeneity of enhancement, amount of enhancement, enhancement pattern over time), tumor margin, location of tumor center, intratumoral calcification, perinephric changes, and patient age and sex. The predictive value of each CT finding was determined by using multivariate logistic regression analysis. RESULTS: Homogeneous enhancement (observed in 79% of AMLs vs 5% of RCCs; odds ratio, 37) and prolonged enhancement pattern (observed in 58% of AMLs vs 10% of RCCs; odds ratio, 42) were valuable predictors for differentiating AML with minimal fat from RCC at multivariate analysis (P <.05 for both). When both CT findings were used as a criterion for differentiating AML from RCC, positive and negative predictive values were 91% (10 of 11 tumors) and 87% (61 of 70 tumors), respectively. Fifty-three percent of AMLs versus 13% of RCCs showed high tumor attenuation on unenhanced scans (P =.04), whereas RCCs showed greater mean enhancement than AMLs (114 HU +/- 44 [SD] vs 73 HU +/- 30 in corticomedullary phase and 66 HU +/- 24 vs 49 HU +/- 20 in early excretory phase) and a male predominance (male-to-female ratio, 50:12 vs 8:11; P =.001). CONCLUSION: Biphasic helical CT may be useful in differentiating AML with minimal fat from RCC, with homogeneous tumor enhancement and prolonged enhancement pattern being the most valuable CT findings.     

动态增强CT扫描对常见肾细胞癌亚型的鉴别诊断价值

目的研究三种常见肾细胞癌(RCC)亚型在动态增强CT扫描中的异同点,以提高CT扫描对于常见RCC亚型的诊断价值。方法回顾性分析141例经手术病理证实的RCC患者的CT平扫及双期扫描的影像资料,测量瘤灶平扫和动态增强扫描的CT值、记录平扫CT表现、强化方式,重点分析CT动态增强扫描中各种亚型之间的异同。结果透明细胞癌(CCRCC)101例,乳头状肾细胞癌(PRCC)27例,嫌色细胞癌(CRCC)13例。CCRCC不均匀强化多于其他两种亚型的RCC(P<0.05),强化程度明显高于其他两种亚型的RCC(P<0.05),转移及形成癌栓的比例较大;PRCC及CRCC强化程度均较低,二者强化程度有类似(P>0.05),但CRCC钙化率较CCRCC和PRCC高,中心无强化瘢痕及轮辐状强化仅见于5个PRCC和1个PRCC。结论皮髓期强化能区别透明细胞癌和非透明细胞癌,结合其他征象有助于鉴别PRCC和CRCC。     

Renal Cortical Tumors: Use of Multiphasic Contrast-enhanced MR Imaging to Differentiate Benign and Malignant Histologic Subtypes

Purpose: To investigate the use of quantitative multiphasic contrast material-enhanced magnetic resonance (MR) imaging in differentiating between common benign and malignant histologic subtypes of renal cortical tumors. Materials and Methods: The institutional review board waived informed consent and approved this retrospective HIPAA-compliant study of 138 patients who underwent preoperative contrast-enhanced MR imaging during the period of January 2004-December 2008. At surgery, 152 renal tumors were identified (77 clear cell, 22 papillary, 18 chromophobe, and 10 unclassified carcinomas; 16 oncocytomas; nine angiomyolipomas). Three readers independently identified and measured the most-enhanced area in each tumor and placed corresponding regions of interest in similar positions on images from the precontrast, corticomedullary, nephrographic, and excretory phases. The percentage change in signal intensity (%SI change) between precontrast imaging and each postcontrast phase was calculated. Interreader agreement was evaluated by using the overall concordance correlation coefficient (OCC). A linear mixed-effects model was used to estimate and compare the trajectories of the means of log %SI change across all phases between the six histologic subtypes. Results: Interreader agreement was substantial to almost perfect (OCC, 0.77-0.88). The %SI change differed significantly between clear cell carcinomas and papillary and chromophobe carcinomas in all phases of enhancement (P < .0001-.0120). In addition, %SI change was significantly higher in angiomyolipomas than in clear cell carcinomas, but only in the corticomedullary phase (P = .0231). Enhancement did not differ significantly between clear cell carcinoma and oncocytoma in any phase (P = .2081-.6000). Conclusion: Quantitative multiphase contrast-enhanced MR imaging offers a widely available, reproducible method to characterize several histologic subtypes of renal cortical tumors, although it does not aid differentiation between clear cell carcinomas and oncocytomas. ? RSNA, 2012.     

Analysis of changes in attenuation of proven renal cysts on different scanning phases of triphasic MDCT

OBJECTIVE: The purpose of this study is to document changes in attenuation values on triphasic MDCT of histologically or surgically proven cystic renal lesions. MATERIALS AND METHODS: A retrospective study of all renal lesions greater than 1 cm that underwent triphasic MDCT was performed in 90 patients before partial nephrectomy. Three reviewers independently measured the mean attenuation of all lesions in three phases (unenhanced, corticomedullary, and parenchymal) in a blinded retrospective fashion. Forty-three lesions identified at CT in 27 patients had pathologic or surgical confirmation as cysts (fluid-filled lesions). Mean change in attenuation between phases was calculated and correlated with size, unenhanced density, and percentage of the lesion exophytic from renal parenchyma. All scans were obtained after 150 mL of nonionic contrast material was injected at 3 mL/sec. Scanning delays were 30-40 sec (corticomedullary phase) and 120 sec (parenchymal phase). RESULTS: The mean change in attenuation coefficient of the cysts from the unenhanced to the parenchymal phase was -1.8 H (SD, +/- 4.4 H); from the unenhanced to the corticomedullary phase was -2.3 H (+/- 3.9 H); and from the corticomedullary to the parenchymal phase was 0.6 H (+/- 4.2 H). No cyst increased more than 10 H between the unenhanced and the parenchymal phases; more than 95% of cysts increased less than 8 H between any scanning phases. No significant difference was seen in enhancement related to lesion size (p > 0.054), unenhanced attenuation (p > 0.255), or percentage of the lesion that was exophytic (p > 0.124). CONCLUSION: The attenuation coefficient of a cystic renal lesion increased by no more than 10 H among the unenhanced, corticomedullary, and parenchymal phase scans.     

长径≤4cm乏脂肪型血管平滑肌脂肪瘤与肾透明细胞癌的CT鉴别

目的：提高对长径≤4cm的乏脂肪型血管平滑肌脂肪瘤（AML）和肾透明细胞癌的CT诊断准确性。方法：对长径≤4cm的14例（16个病灶）乏脂肪型AML和16例（16个病灶）肾透明细胞癌的CT形态学表现（楔形征、肿瘤位置、钙化、假包膜及瘤内血管）及平扫、增强CT值进行测量及分析,所有肿瘤均经手术病理证实。结果：两组中楔形征（P=0．023）、瘤内血管（P=0．029）、假包膜（P=0．023）、平扫CT值（P〈0．001）、皮髓质期及排泄期的绝对强化值（分别P=0．009和0．044）及相对强化幅度（分别P=0．008和0．020）的差异有统计学意义,其中两期的相对强化幅度的Pear—SOIl相关系数（r=0．461和=0．409）较绝对强化值（r=0．456和-0．366）高。而钙化（P=0．484）及肿瘤位置（P=0．473）在两组间的差异无统计学意义（P〉0．05）。排泄期CT相对强化幅度〉-19．2％时,诊断乏脂肪型AML的特异度及敏感度分别为87．5％和25．0％。结论：乏脂肪型AML中楔形征多见,瘤内血管、假包膜少见;其平扫CT值较透明细胞癌病灶高,与竖脊肌相似,皮髓质期相对强化幅度较透明细胞癌低,排泄期对比剂退出较少,其中肿瘤的CT相对强化幅度对诊断更有意义。     

小肾癌在64层螺旋CT多期增强扫描中的影像特征

目的研究小肾癌在64层螺旋CT多期动态扫描中的影像特征。方法 20例经手术病理证实的小肾癌患者,包括透明细胞癌18例,嫌色细胞癌及乳头状细胞癌各1例,术前均经增强前与增强后皮质期、实质期以及排泄期扫描,全部操作是采用GELight-speed 64层螺旋CT机进行的。对所有患者的CT表现进行了回顾性分析。结果 20例小肾癌患者均为单发,左侧9例,右侧11例,肿瘤平均直径2.3±0.4 cm(范围1.6～2.9 cm)。局限于肾内4例,突出于肾轮廓外16例,但无1例伴发肾周、肾静脉或下腔静脉受侵及淋巴结转移。CT平扫检出16例,其中13例的瘤体呈低密度,增强后皮质期及实质期20例全部检出,其中18例的瘤体明显强化。皮质期瘤体CT值低于或达到对侧正常肾皮质,实质期瘤体CT值下降,排泄期瘤体CT值进一步下降,呈低密度影,表现为"快进快出"的强化形式。结论 64层螺旋CT多期扫描能直观、立体地显示小肾癌的部位、大小及其与周围结构的关系,尤其是它的时相特征对于术前确诊和制定手术方案至关重要。     

肾细胞癌的CT影像特征与病理分型

目的：联合病理分型对肾细胞癌的CT影像特征进行分析以提高诊断的准确性。方法收集我院手术病理证实的47例肾细胞癌患者,术前均做CT平扫＋动态增强扫描,回顾性分析CT影像特征并与病理结果对照分析。结果34例透明细胞癌,5例多房囊性肾细胞癌,3例乳头状癌,4例嫌色细胞癌,1例集合管癌。最新病理分型将颗粒细胞癌和多房囊性肾细胞癌均归到透明细胞癌,此类型肾癌血供丰富,增强扫描后动脉期明显强化;而乳头状癌和嫌色细胞癌血供相对较少,强化程度明显低于透明细胞癌。结论各型肾细胞癌的CT表现的特异性并不强,最终分型仍依靠病理,仔细分析肾癌的CT影像特征与病理之间的关系有助于诊断与鉴别。     

Different phases of renal enhancement: role in detecting and characterizing renal masses during helical CT.

Although helical CT offers greater flexibility in data acquisition and reconstruction than does conventional axial CT, new opportunities for error must be understood so that optimal protocols are used that minimize the likelihood of misdiagnosis. Most nonrenal abdominal helical CT scans are obtained late in the corticomedullary phase of renal enhancement because of the preferable enhancement of other parenchymal organs. CT evaluation of the kidneys during the corticomedullary phase or at an intermediate phase between the corticomedullary and nephrographic phases has significant limitations. Therefore, dedicated renal CT performed for the detection of suspected renal masses or for the characterization of known renal masses must include images obtained during later phases of enhancement (i.e., nephrographic or excretory phase). Nephrographic or excretory phase images appear to be similar to one another but superior to corticomedullary phase images in the ability to both detect and characterize renal masses. Corticomedullary phase images should always be obtained when information about the renal vasculature is desired or when there is a possibility that a detected renal mass may represent an aneurysm or an arteriovenous malformation or fistula. Optimal technique of helical CT for staging renal cancers may require use of both corticomedullary and nephrographic or excretory phase images, although work in this area is still preliminary.     

Collecting duct carcinoma of the kidney: CT and pathologic correlation

PURPOSE: We characterized CT findings of collecting duct carcinoma of the kidney and correlated these with the histopathologic findings. MATERIALS AND METHODS: CT scans of 18 patients with pathologically proven collecting duct carcinoma of the kidney were retrospectively reviewed. We analyzed CT findings of collecting duct carcinoma and also correlated CT findings with the histopathologic findings. RESULTS: The mean size of the tumors was 6.9 cm and all cases were solid. Seventeen (94%) tumors had a medullary location. Nine (69%) and 11 (85%) cases showed weak and heterogeneous enhancement, respectively. A cystic component (50%) was frequently seen within the tumors. Lymphadenopathy and metastasis were noted in 10 (56%) and 6 (33%) cases, respectively. Perinephric stranding and vascular invasion were present in 10 (56%) and 5 (28%) cases, respectively. In 17 (94%) of the 18 cases, involvement of the renal sinus was present. Infiltrative growth (67%) and preservation of the renal contour (61%) were more common than expansile growth (33%) and exophytic configuration (39%), respectively. These CT features were well correlated with the histopathologic findings. CONCLUSION: Medullary location, weak and heterogeneous enhancement, involvement of the renal sinus, infiltrative growth, preserved renal contour, and a cystic component are CT findings frequently seen in patients with collecting duct carcinoma of the kidney. CT findings are nevertheless nonspecific and do not allow collecting duct carcinoma to be easily differentiated from the other subtypes of renal cell carcinoma. However, when CT demonstrates a renal tumor with these findings, collecting duct carcinoma can be considered in the differential diagnosis.     

增强CT参数在肾癌术前病理分型中的价值

目的:探讨肾癌(RCC)在增强CT各期中的表现及增强CT参数在肾癌术前病理分型中的价值.方法:回顾性分析149例肾癌(包括透明RCC 131例、乳头状RCC 12例和嫌色RCC6例)患者的四期CT(平扫期、皮质期、实质期及排泄期)扫描图像,结合术后病理进行对比分析,比较各期肾癌绝对增强值、病灶强化百分比、峰值出现时相等参数.结果:透明RCC CT值峰值出现于皮质期,且此期透明RCC的CT值明显高于同期的乳头状RCC和嫌色RCC,差异有统计学意义(P＜0.05);乳头状RCC及嫌色RCC的CT峰值出现于实质期.皮质期透明RCC的CT绝对增强值、病灶强化百分比均明显高于乳头状RCC及嫌色RCC,差异有统计学意义(P＜0.05),而排泄期嫌色RCC绝对增强值高于乳头状RCC,差异有统计学意义(P＜0.05).结论:CT绝对增强值、病灶强化百分比等增强CT参数可与传统CT诊断方法相结合,提高肾癌术前病理分型的诊断准确度.     

肾皮髓期增强扫描对肾细胞癌亚型的鉴别诊断价值

目的　评价CT、MRI肾皮髓期增强扫描对肾细胞癌亚型的鉴别诊断价值。方法　对 96例肾细胞癌患者的肾脏行CT和 /或MRI肾皮髓期增强扫描。结果　肿瘤直径为 2~9cm,经手术病理证实为肉瘤样肾细胞癌 1例、透明细胞癌 78例、颗粒细胞癌 5例、混合细胞癌 8例和乳头状癌 4例。肾皮髓期增强扫描,肉瘤样肾细胞癌、混合细胞癌、97. 4% (76 /78)的透明细胞癌和 75. 0% (3 /4)的乳头状癌呈不均匀强化,而颗粒细胞癌强化较均匀。51. 3% (40 /78)的透明细胞癌及 37. 5% (3 /8)的混合细胞癌强化程度强于邻近肾皮质;肉瘤样肾细胞癌、44. 9% (35 /78)的透明细胞癌和 50. 0% (4 /8)的混合细胞癌强化程度与邻近肾皮质相仿; 3. 8% (3 /78)的透明细胞癌、12. 5% (1 /8)的混合细胞癌及所有乳头状癌和颗粒细胞癌强化程度明显弱于邻近肾皮质。结论　各型肾细胞癌在CT/MRI肾皮髓期增强扫描上有不同的表现,有助于鉴别诊断。     

Enhancement characteristics of papillary renal neoplasms revealed on triphasic helical CT of the kidneys.

OBJECTIVE: The purpose of this study was to determine whether renal tumor enhancement or heterogeneity on triphasic helical CT scans is predictive of the papillary cell subtype or nuclear grade of renal cell carcinoma. MATERIALS AND METHODS: We reviewed the CT scans of 90 consecutive patients with renal masses who had undergone triphasic renal helical CT before a complete or partial nephrectomy (12 with papillary renal cell carcinomas, 66 with nonpapillary renal cell carcinomas, and 12 with benign lesions). Three radiologists who were unaware of the patients' diagnoses retrospectively and independently measured the attenuation of each patient's tumor, abdominal aorta, and normal renal parenchyma on the scans obtained during all three phases. Ratios of tumor-to-aorta enhancement and tumor-to-normal renal parenchyma enhancement were calculated for both of the phases performed after contrast material had been administered. Tumor heterogeneity was calculated as the difference between the highest and lowest attenuation values divided by the value of the enhancement of the aorta. Values were correlated with cell type and nuclear grade found at surgical pathology. RESULTS: Low tumor-to-aorta enhancement and low tumor-to-normal renal parenchyma enhancement ratios on the vascular phase scans significantly correlated (p < 0.001) with papillary renal cell type carcinoma. Homogeneity and tumor-to-parenchyma enhancement ratios on the parenchymal phase scans also significantly correlated (p < 0.001) with papillary renal cell type carcinoma. Heterogeneity and tumor enhancement ratios did not correlate with the nuclear grade of the carcinoma. CONCLUSION: Papillary renal cell carcinomas are typically hypovascular and homogeneous. A high tumor-to-parenchyma enhancement ratio (> or = 25%) essentially excludes the possibility of a tumor being papillary renal cell carcinoma. A low tumor-to-aorta enhancement ratio or tumor-to-normal renal parenchyma enhancement ratio is more likely to indicate papillary renal cell carcinoma.     

肾癌少见亚型的多层螺旋CT特征

目的 探讨多层螺旋CT(MSCT)对肾癌少见亚型的诊断价值.方法 收集第三军医大学大坪医院经病理证实的除透明细胞癌外的所有肾癌资料,包括嫌色细胞癌(ChRCC)14例,乳头状癌(PRCC)Ⅰ型10例,PRCCⅡ型15例,黏液样小管状和梭形细胞癌(MTSCC)7例,对比分析所有CT征象和强化特点.结果 4种肾癌亚型在强化均匀度、边界、有无侵犯肾盂、肿瘤内血管影等指标上的差异有统计学意义,ChRCC在三期增强扫描的CT值均高于其他3种肾癌亚型,分别与PRCCⅠ型、PRCCⅡ型和MTSCC的差异有统计学意义(P<0.05).仅MTSCC在增强各期的强化程度都低于肾髓质,其余亚型在皮质期的强化程度均高于肾髓质.结论 MSCT结合增强扫描在上述4种肾癌亚型的鉴别诊断中有着较高的临床应用价值.